WO2020082454A1

WO2020082454A1 - Method for effectively accessing flash block state management table in flash storage device

Info

Publication number: WO2020082454A1
Application number: PCT/CN2018/115515
Authority: WO
Inventors: 黄中柱; 李庭育; 魏智汎; 张盛豪
Original assignee: 江苏华存电子科技有限公司
Priority date: 2018-10-24
Filing date: 2018-11-14
Publication date: 2020-04-30
Also published as: CN109408408A

Abstract

A method for effectively accessing a flash block state management table in a flash storage device, comprising the following steps: step one: first determining a segmentation of the currently used block; step two: increasing one for the hit rate of the segmentation; step three: determining whether the segmentation is comprised in the memory, if yes, directly ending; if not, entering the next step; step four: determining whether to write the memory segmentation back to the flash, if yes, entering the next step; if not, skipping to step six; step five: determining, according to the hit rate, the segmentation written back to the flash; and step six: reading the segmentation related to the currently used block from the flash, and placing same into the memory. The method can effectively manage the block state management table, decrease the times of reading of the flash, avoid accelerating the loss of the flash, and significantly improve the execution efficiency.

Description

Method for effectively accessing state management table of flash memory block in flash memory storage device

Technical field

The invention relates to the technical field of storage devices, in particular to a method for effectively accessing a flash memory block state management table in a flash memory storage device.

Background technique

Flash memory is a long-life non-volatile memory. Data deletion is not in a single byte but in fixed blocks. The block size is generally 256KB to 20MB. Flash memory is electronically erasable only. A variant of read memory (EEPROM). Flash memory is different from EEPROM in that EEPROM can be deleted and rewritten at the byte level instead of the entire chip erase and write, and most chips of flash memory require block erase.

There are n blocks in the flash memory, and each block will have a different state according to needs, including unused or used, and the used blocks have various states according to different tasks. Therefore, a block status management table is needed to record information. When the storage device is powered off, the block status management table can be used to reconstruct the usage status of the blocks in the entire storage device.

The flash block state management table will be recorded in memory. When the memory space cannot meet the size of the flash block state management table, the flash block state management table will be cut into several segments, and each segment records the corresponding block state.

Memory is one of the important components in a computer, and it is a bridge to communicate with the CPU. All programs in the computer are run in memory, so the performance of the memory has a great impact on the computer. The internal memory is also called internal memory. Its function is to temporarily store the calculation data in the CPU and the data exchanged with external storage such as hard disk. As long as the computer is running, the CPU will transfer the data that needs to be calculated to the memory for operation. When the operation is completed, the CPU will transfer the results. The operation of the memory also determines the stable operation of the computer. The memory is composed of memory chips and circuits. Board, gold finger and other parts.

Memory, also known as main memory, is a storage space that the CPU can directly address and is made of semiconductor devices. The characteristic of memory is fast access rate. Memory is the main component of a computer, and it is relative to external storage. The programs we usually use, such as the Windows operating system, typing software, game software, etc., are generally installed on external storage such as hard disks, but this is not the function, they must be transferred to the memory to run To really use its functions, we usually enter a piece of text or play a game, which is actually done in memory. Memory is where the programs and data are temporarily stored. For example, when we are using WPS to process documents, when you are on the keyboard When you type in a character, it will be stored in the memory. When you choose to save, the data in the memory will be saved in the hard disk.

Only the segment of the currently accessed block is saved in the memory, and the other segments are stored in the flash memory. When the segment in the memory is not related to the currently used block, the updated content of the segment needs to be stored in the flash memory and related The segment is taken from the flash memory and put into the memory. This method increases the number of flash memory reads and writes, which is easy to cause the loss of the flash memory and increase the read and write time. This problem exists.

Summary of the invention

The object of the present invention is to provide an effective access method for a flash block state management table in a flash storage device, which can effectively manage the block state management table, reduce the number of reads of the flash memory, avoid accelerating the loss of the flash memory, and greatly improve the execution efficiency, Solve the problems raised in the background art mentioned above.

In order to achieve the above object, the present invention provides the following technical solution: A method for effectively accessing a flash memory block state management table in a flash memory storage device, including the following steps:

Step 1: First confirm the segmentation of the currently used block;

Step 2: The hit rate of this segment is +1;

Step 3: Confirm whether this segment exists in the memory, if yes, directly end, if not, go to the next step;

Step 4: Confirm whether to write the memory segment back to the flash memory, if yes, go to the next step, if no, skip to step 6;

Step 5: Determine the segment to write back to the flash memory according to the hit rate;

Step 6: Read the segment related to the currently used block from the flash memory and put it in the memory.

Preferably, in step three, several segments are stored in the memory and it is determined which segment is to be written back to the flash memory according to the segment hit rate.

Preferably, there are several blocks in the memory in step four.

Preferably, in step one, the blocks have different states according to requirements. The blocks include unused or used, and the used blocks have various states according to different tasks.

Compared with the prior art, the beneficial effects of the present invention are:

Can effectively manage the block state management table, reduce the number of flash memory reads, avoid accelerating the loss of flash memory, and greatly improve the execution efficiency.

BRIEF DESCRIPTION

Figure 1 is a schematic diagram of the process of the present invention.

FIG. 2 is a schematic diagram of replacing two segments by storing two segments in memory.

Fig. 3 is a schematic diagram showing the replacement of segments in a conventional manner.

detailed description

The technical solutions in the embodiments of the present invention will be described clearly and completely in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts fall within the protection scope of the present invention.

Referring to FIG. 1, the present invention provides a technical solution: a method for effectively accessing a flash memory block state management table in a flash memory storage device, including the following steps:

Step 1: First confirm the segmentation of the currently used block;

Step 2: The hit rate of this segment is +1;

Store several segments in the memory and decide which segment to be written back to the flash memory according to the hit rate of the segment. There are several blocks in the memory, and there are different states according to the requirements. The blocks are included as unused or It is used, and the used block has various states according to different tasks.

In the first embodiment, as shown in FIG. 2, two segments are now stored in the memory, and which segment is to be written back to the flash memory is determined according to the segment hit rate. If segment a-> segment c-> Segment a-> Segment d has been repeatedly looping this situation, the segment a is stored in the memory first, and then the segment c is stored, because the segment a does not need to be taken from the flash memory in the memory, and then according to the hit rate Write the segment c back to the flash memory, and then put the segment d read out in the memory, greatly improving the execution efficiency.

The second embodiment, as shown in FIG. 3, the traditional way: if the block-related block state management table segment usage order is: segment a-> segment c-> segment a-> segment d has been repeatedly looped, The flow of this operation will become segment a write to flash memory, read segment c from flash memory, then write segment c to flash memory, read segment a from flash memory, and then segment a Writing to the flash memory, and then reading the segment d into the memory, has been repeated, which increases the number of flash memory reads and writes, the loss of the flash memory is higher than that of the first embodiment, and the reading and writing time is longer than the first embodiment.

Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, and substitutions can be made to these embodiments without departing from the principle and spirit of the present invention And variations, the scope of the invention is defined by the appended claims and their equivalents.

Claims

A method for effectively accessing a flash memory block state management table in a flash memory storage device is characterized by comprising the following steps:

Step 1: First confirm the segmentation of the currently used block;

Step 2: The hit rate of this segment is +1;

Step 3: Confirm whether this segment exists in the memory, if yes, directly end, if not, go to the next step;

Step 4: Confirm whether to write the memory segment back to the flash memory, if yes, go to the next step, if no, skip to step 6;

Step 5: Determine the segment to write back to the flash memory according to the hit rate;

Step 6: Read the segment related to the currently used block from the flash memory and put it in the memory.
The method for effectively accessing a flash block state management table in a flash storage device according to claim 1, characterized in that: in step three, a number of segments are stored in the memory and determined according to the relative hit rate of the segments Which segment is to be written back to flash memory.
The method for effectively accessing a flash memory block status management table in a flash memory storage device according to claim 1, wherein there are several blocks in the memory in step four.
The method for effectively accessing a flash memory block status management table in a flash memory storage device according to claim 1, wherein: in step 1, the blocks have different states according to requirements, and the blocks are included as unused or It is used, and the used block has various states according to different tasks.